There's a piece of metal that is called "End Wall" you attach it to the house and overlap the metal of the building. There's a foam gasket that is shaped like the metal that you stick to the roof under the end wall. Then use silicone caulk along the top edge of the end wall where it meets the house.
Since aluminum is rather light, you might want to look into fasteners or screws, or rivets. It would, however, be best if you talked to a roofing expert or contractor for professional advice on the same.